1. Field of the Invention
The present invention relates to a document verification method, a document verification apparatus, and a storage medium in which a document verification program is stored.
2. Description of the Related Art
With the development of the information society, it has been common to store electronic data created by a word processor and the like or electronic data obtained by scanning a paper document with a copying machine and digitizing the data into a document management system and the like.
Recently, with the rise of consciousness of security, it has become increasingly common to give an electronic signature to such an electronic document to show the identity of a person who gives the signature or confirm that the electronic document has not been falsified or to give a timestamp to certify the existence of the electronic document. In Japanese Patent Laid-Open No. 2005-159492, it is described to visualize time information included in an electronic signature so that the time when the electronic signature is given can be easily confirmed.
In such a situation, a technique for collectively verifying signatures in a document to which multiple signatures and timestamps are given is gradually utilized. Furthermore, with the increase in the number of documents to which signatures and timestamps are given, a technique for collectively verifying a lot of such documents by a document management system is also gradually utilized.
Since, in such a system, the number of signature verification results is very large, the verification results are collectively notified to a user.